Feed water control



March 31, 1942.

s. s. VAN scOY FEED WATER CONTROL 'Filed June 1:5, 1959 E l INVENTOR mwa 6. Mw 5cm. '725x da@ AToRNY.

Patented Mar. 31, 1942 UNITED STATES PATENT OFFICE FEED- WATER CONTROL Samuel S. Van Scoy, Hobart, Ind.

Application June 13, 1939, Serial N0. 278,936

Claims.

My invention relates to improvements in feed watercontrols and it more especially consists of the features pointed out in the annexed claims.

The purpose of my invention is to guard against the introduction of yfeed water directly into the steam drum or steam space of a boiler; to provide a water trap or seal to prevent contact between the water being fed to the boiler and the steam in the boiler until the moment of discharge of the water into the steam space of the boiler occurs; to keep the point of discharge into the steam space of the boiler at as low a temperature as water flowing through the discharge to prevent the heat from precipitating out of solution the bicarbonates in the water which would form scale at this point of discharge; and to discharge the incoming water at an even rate at any one point or over the entire length of said steam drum or steam space of a boiler.

With these and other ends in view I illustrate in the accompanying drawing such instances of adaptation as will disclose the broad features of the invention without limiting myself to the specific details shown thereon and described herein conformable to the annexed l claims.

Fig. 1 is a side elevation partly in section of my continuous water supply.

Fig. 2 is Aa bottom plan view of Fig. 1 with portions broken out and sectioned.

Fig. 3 is a transverse elevation on line 3-3 of Fig. l.

Fig. 4 is a diagrammatic elevation of a modification in which the admission of Water is at Aapproximately right angles to the direction of admission shown in Fig. 1.

Fig. 5 is a diagrammaticlelevation showing my device associated with a conventional cross drum type of boiler.

In the practice of my invention I may use whatever alternatives or equivalents of structure that the exigencies of varying conditions may demand without departing from the broad spirit of the invention.

A conventional cross drum type of steam boiler is shown diagrammatically in Fig. 5. The water tube I extends lengthwise of the drum I3, in the water space of the drum which is connected to a conventional boiler lli asindicated by the legend To Boiler in Fig. 1.

Feed water is introduced into the steam space of a boiler, the water falling through the steam space in intimate contact with the steam tends to give up its dissolved gases to the out-going steam, eliminating the corrosive effect of these gases on the tubes and shell of the boiler.

Keeping the points of discharge of the Water into the steam space at as low a temperature as the incoming Water prevents the heat from precipitating out of solution the bi-carbonates in the water, which if not prevented would form scale at this point and retard the flow of Water into the boiler.

The seal 6-1 prevents contact between the incoming water and the steam, until the moment of discharge of the water into the steam space of -the boiler, and thereby eliminates the knocking or rapping noise commonly known as water hammer that occurs when steam under pressure comes in contact in 'a confined space with water of a lower temperature than the steam.

The water level is maintained as shown approximately at lil in Fig. 1 of the drawing and the feed water enters the boiler continuously. The Water is fed into the boiler uniformly over the whole length of the drum, at spaced apart points, under varying rates of flow.

The advantages I gain by feeding the water evenly over the entirelength ofl the drum of a cross drum boiler is in marked contrast to the following disadvantages:

In ordinary practice the calcium and magnesium bicarbonates in the feed water are broken up at the temperature in the boiler (without the use of chemicals)A into calcium and magnesium carbonates. The calcium carbonate being prac- .tically-insoluble precipitates out of solution at ,these temperatures at once.

The magnesium carbonate is slightly soluble but when concentrated inthe boiler water the excess magnesium carbonate, above its saturation solubility, precipitates out of solution and settles out of suspension, along with the calcium carbonates and any other suspended solids present, and these are deposited upon the heating surface of the boiler in the form of sludge or scale.

If the feed water is chemically treated, the carbonates and also the sulphates are more rapidly precipitated out of solution.

`When feeding the water into the cross drum type of boiler at one point or section, these solids will concentrate in this section and, the greater the concentration of solids, the quicker they will settle out of suspension. In addition the cooling action of the incoming water will tend to slow down the circulation of the water in this section of the boiler which further accelerates the settling out of these suspended solids upon the heating surface of the boiler in the form of scale or sludge.

In contrast to the foregoing, by feeding the water evenly over the whole length of the boiler drum, the concentration of suspended solids are distributed evenly, and the speed of circulation is the same over every portion of the boiler thus tending to keep these solids in suspensionnot precipitateduntil they can be removed through the conventional blow down valve.

In a horizontal fire tube boiler it is desirable to feed the water into the steam space of a boiler at a point or points that will tend to accelerate the circulation.

I use a tubular casing or distributor I provided with suitable heads 2. These heads support vthe pipe 3 through which the incoming water passes. This pipe has a number of side openings 4leading into the open inner space of the casing. The pipe 3 shown in Figs. l, 2 and 3 and the pipe I2 in Fig. 4 support the distributor I in the steam space of any-desired type of boiler by passing through the external walls of the boiler in any conventional manner positioning a distributor above the normal water level of the boiler.

At one side of the water pipe 3 and relatively centralof the casing a series of exit pipes 5 are placed. These are directly in the steam space of the boiler. The upper ends of the tubes 5 are formed in the shape of V-slots 9, directly opposite each other. The portion Il of the upper end of the tubes 5 that is not cut away by the slots 9 is in engagement with the upper wall 1. This is clearly shown in Figs. l and 3. The side Walls 6 are spaced from the pipe 5 to form an annular l opening 8 for the free admission of water into the inside of the cap and out through the slots 9.

The water level I0 in the casing is above the bottom of the V-slots 9 which serves as a trap, or Vin engineering parlance, a seal against steam passing upward through the tubes 5 and out through V-slots 9.

It is immaterial whether the entering water pipe is positioned as shown in Fig. 1 or whether 'it enters the casing at right angles as shown in Fig. 4.

From this structure it is apparent that the purposes recited above, will be attained.

What I claim is:

l. In feed water controls positioned in the steam space of steam boilers, a suitable casing, a water inlet tube to the casing, such inlet having a plurality of separate openings at spaced apart points throughout the length of the tube, a plurality of separate exit tubes in approximate radial relation to the center of the casing, such tubes terminating through a wall of the casing and leading into the steam space of a boiler, a cap having an open bottom and a closed top positioned against the upper end of each tube, and V-shaped slots in the wall of the exit tubes at the upper end of the tube, the bottom of the V being above the plane of the lower edge of the cap to thereby form a seal.

2. In controls for admitting feed Water into the steam space of boilers, an enclosing casing, a water supply Ytube within the casing terminating outside of the `casing and passing through the external walls of said casing, said tube having openings within its walls leading into the interior of the casing, a plurality of separate tubes positioned adjacent said water tube and projecting through the casing at one side thereof, and means forming water level seals at the upper ends of the exit tubes to prevent steam flowing against incoming water.

steam space of a boiler comprising a casing servlsteam -space of a, boiler comprising a casing seraing as a distributor, a water inlet from the outside of the casing to its inside, said inlet having a plurality of openings connecting the inside of the inlet to the inside of the casing, a plurality of exit tubes from the casing, and means forming a v steam trap at the upper end of such tubes adapted to prevent contact between the incoming water and the steam until the moment of discharge of the water from said tubes into the steam space of the boiler.

4. The process of uniformly feeding water into the steam space of a steam boiler which consists in supplying water at an even rate on the same level at desired spaced intervals into a distributor, in continuously removing the Water at different points on approximately the same level from the distributor to feed water into the steam space of a boiler, and in -preventing flow of steam at the same level in a reverse direction to the movement of the water.

5. In feed water controls positioned in the steam space of steam boilers, an enclosing casing, a water supply tube within the casing terminating outside thereof, said tube being positioned normally beneath the water level and having openings within its walls leading into the interior of the casing, a plurality of separate tubes positioned adjacent the water supplytube and pro- `jecting through the casing at one side thereof,

and means forming Water level seals at the upper ends of the tubes to prevent steam flowing against the incoming water whereby the temperature at the `point of discharge will be approximately as low as that of the incoming water.

SAMUEL S. VAN SCOY.

CERTIFICATE CORRECTION.

Patent No. 2,278,0h8. rr'rArch51, 19m..

SAMUEL s. VAN scoY..

It is hereby certified that error appears in the printed specifioetion of the above numbered patent requiring correction as follows: Page 2, secon@ column, line 20, before the word "steam" insert 5. A feed vivater Control positioned Within the; line 21, strike out "steam space of b011- and that the gaio Z Letters Patent shoulcl'be er comprising-a casing seranform to the record read with this correotion therein that the same may co of the case in the Patent Office. 'i'

signed and sealed this 16th day of June, A. D. 191g.

Henry Van Arsdale (Seal) Acting Commi ss ioner of Patent s 

